James Frysinger wrote in USMA 22673: >Folks, > >I"ve spent some time recently working on the editing of IEEE standards and >that got me digging again into other standards, especially the SI Brochure. > >Being in an editorial frame of mind, I got to musing about what revisions I >would like to see in the next draft of the SI brochure. One that comes to >mind is that I would like to see an explicit statement in the brochure about >the inclusion of a space between the numerical portion and the unit portion >of a quantity. As it stands, all that is there is the obvious use of this >construction, so that we see > 273.15 K not 273.15K (p. 96) >This could be placed in clause 5.3.
D'accord! A common error in the UK is to omit the space. Does 32lm mean 321 metres or 32 lumens? But I would like an exception to be made in the case of the degree Celsius. In the case of angles, 30� is correct, but 30�C is considered to be incorrect. Why? There is no possibility of misunderstanding. We are faced here with two competing anomalies: either anomalous treatment of the degree symbol or an exception for the degree Celsius among metric units. A possible solution would be to rename the "degree Celsius" as simply the "celsius". > I would also like to see an explicit statement regarding the relative >preference of the raised dot and the thin non-breaking space as separators of >unit factors in a derived unit. The preferred use seems to be the raised dot >as shown by example throughout the text but clause 5.3 states no preference. >That may be intentional; I do not know. The (Canadian) Technical Committee on International System of Units (SI) was unable to reach a consensus on this question. The (Canadian) Metric Practice Guide Z234.1-00 states: 4.8 Units Formed by Multiplication or Division ..............................................................................4.8.4 When names of units are used, multiplication shall be indicated by a space in English, by a hyphen in French. Example In English, write pascal second; in French, write *pascal-seconde*. > I would like to see an explicit statement in the brochure >that derived units >are SI units, as are the base units. Further, that "SI units" and "units of >the SI" are synonymous. (Are those two English constructions distinguishable >in French? I think that they are.) Those units are "SI derived units" as distinct from the "SI base units". I suspect that the term "units of the SI" was an American attempt to create a term to include both classes of units. I can't find it in the SI brochure, in English or French. The inclusive term is simply "SI units". >Joseph B. Reid 17 Glebe Road West Toronto M5P 1C8 Telephone 456-486-6071
